public ContinueForRewriter(VBS.ForBlockSyntax vbFor, string gotoLabel)
{
if (vbFor == null)
{
throw new ArgumentNullException("vbFor");
}
this._vbFor = vbFor;
this.Label = gotoLabel;
}
public override SyntaxList <StatementSyntax> VisitForBlock(VBSyntax.ForBlockSyntax node)
{
var stmt = node.ForStatement;
ExpressionSyntax startValue = (ExpressionSyntax)stmt.FromValue.Accept(nodesVisitor);
VariableDeclarationSyntax declaration = null;
ExpressionSyntax id;
if (stmt.ControlVariable is VBSyntax.VariableDeclaratorSyntax)
{
var v = (VBSyntax.VariableDeclaratorSyntax)stmt.ControlVariable;
declaration = SplitVariableDeclarations(v, nodesVisitor, semanticModel).Values.Single();
declaration = declaration.WithVariables(SyntaxFactory.SingletonSeparatedList(declaration.Variables[0].WithInitializer(SyntaxFactory.EqualsValueClause(startValue))));
id = SyntaxFactory.IdentifierName(declaration.Variables[0].Identifier);
}
else
{
var v = (ExpressionSyntax)stmt.ControlVariable.Accept(nodesVisitor);
startValue = SyntaxFactory.AssignmentExpression(SyntaxKind.SimpleAssignmentExpression, v, startValue);
id = v;
}
var step = (ExpressionSyntax)stmt.StepClause?.StepValue.Accept(nodesVisitor);
PrefixUnaryExpressionSyntax value = step.SkipParens() as PrefixUnaryExpressionSyntax;
ExpressionSyntax condition;
if (value == null)
{
condition = SyntaxFactory.BinaryExpression(SyntaxKind.LessThanOrEqualExpression, id, (ExpressionSyntax)stmt.ToValue.Accept(nodesVisitor));
}
else
{
condition = SyntaxFactory.BinaryExpression(SyntaxKind.GreaterThanOrEqualExpression, id, (ExpressionSyntax)stmt.ToValue.Accept(nodesVisitor));
}
if (step == null)
{
step = SyntaxFactory.PostfixUnaryExpression(SyntaxKind.PostIncrementExpression, id);
}
else
{
step = SyntaxFactory.AssignmentExpression(SyntaxKind.AddAssignmentExpression, id, step);
}
var block = SyntaxFactory.Block(node.Statements.SelectMany(s => s.Accept(this)));
return(SingleStatement(SyntaxFactory.ForStatement(
declaration,
declaration != null ? SyntaxFactory.SeparatedList <ExpressionSyntax>() : SyntaxFactory.SingletonSeparatedList(startValue),
condition,
SyntaxFactory.SingletonSeparatedList(step),
block)));
}
public override SyntaxList <StatementSyntax> VisitForBlock(VBSyntax.ForBlockSyntax node)
{
var stmt = node.ForStatement;
ExpressionSyntax startValue = (ExpressionSyntax)stmt.FromValue.Accept(_nodesVisitor);
VariableDeclarationSyntax declaration = null;
ExpressionSyntax id;
if (stmt.ControlVariable is VBSyntax.VariableDeclaratorSyntax)
{
var v = (VBSyntax.VariableDeclaratorSyntax)stmt.ControlVariable;
declaration = CommonConversions.SplitVariableDeclarations(v).Values.Single();
declaration = declaration.WithVariables(SyntaxFactory.SingletonSeparatedList(declaration.Variables[0].WithInitializer(SyntaxFactory.EqualsValueClause(startValue))));
id = SyntaxFactory.IdentifierName(declaration.Variables[0].Identifier);
}
else
{
id = (ExpressionSyntax)stmt.ControlVariable.Accept(_nodesVisitor);
var symbol = _semanticModel.GetSymbolInfo(stmt.ControlVariable).Symbol;
if (symbol != null && !_semanticModel.LookupSymbols(node.FullSpan.Start, name: symbol.Name).Any())
{
declaration = CommonConversions.CreateVariableDeclarationAndAssignment(symbol.Name, startValue);
}
else
{
startValue = SyntaxFactory.AssignmentExpression(SyntaxKind.SimpleAssignmentExpression, id, startValue);
}
}
var step = (ExpressionSyntax)stmt.StepClause?.StepValue.Accept(_nodesVisitor);
PrefixUnaryExpressionSyntax value = step.SkipParens() as PrefixUnaryExpressionSyntax;
ExpressionSyntax condition;
// In Visual Basic, the To expression is only evaluated once, but in C# will be evaluated every loop.
// If it could evaluate differently or has side effects, it must be extracted as a variable
var preLoopStatements = new List <SyntaxNode>();
var csToValue = (ExpressionSyntax)stmt.ToValue.Accept(_nodesVisitor);
if (!_semanticModel.GetConstantValue(stmt.ToValue).HasValue)
{
var loopToVariableName = GetUniqueVariableNameInScope(node, "loopTo");
var loopEndDeclaration = SyntaxFactory.LocalDeclarationStatement(CommonConversions.CreateVariableDeclarationAndAssignment(loopToVariableName, csToValue));
// Does not do anything about porting newline trivia upwards to maintain spacing above the loop
preLoopStatements.Add(loopEndDeclaration);
csToValue = SyntaxFactory.IdentifierName(loopToVariableName);
}
;
if (value == null)
{
condition = SyntaxFactory.BinaryExpression(SyntaxKind.LessThanOrEqualExpression, id, csToValue);
}
else
{
condition = SyntaxFactory.BinaryExpression(SyntaxKind.GreaterThanOrEqualExpression, id, csToValue);
}
if (step == null)
{
step = SyntaxFactory.PostfixUnaryExpression(SyntaxKind.PostIncrementExpression, id);
}
else
{
step = SyntaxFactory.AssignmentExpression(SyntaxKind.AddAssignmentExpression, id, step);
}
var block = SyntaxFactory.Block(node.Statements.SelectMany(s => s.Accept(CommentConvertingVisitor)));
var forStatementSyntax = SyntaxFactory.ForStatement(
declaration,
declaration != null
? SyntaxFactory.SeparatedList <ExpressionSyntax>()
: SyntaxFactory.SingletonSeparatedList(startValue),
condition,
SyntaxFactory.SingletonSeparatedList(step),
block.UnpackNonNestedBlock());
return(SyntaxFactory.List(preLoopStatements.Concat(new[] { forStatementSyntax })));
}
public override SyntaxList <StatementSyntax> VisitForBlock(VBSyntax.ForBlockSyntax node)
{
var stmt = node.ForStatement;
ExpressionSyntax startValue = (ExpressionSyntax)stmt.FromValue.Accept(_nodesVisitor);
VariableDeclarationSyntax declaration = null;
ExpressionSyntax id;
if (stmt.ControlVariable is VBSyntax.VariableDeclaratorSyntax)
{
var v = (VBSyntax.VariableDeclaratorSyntax)stmt.ControlVariable;
declaration = VisualBasicConverter.SplitVariableDeclarations(v, _nodesVisitor, _semanticModel).Values.Single();
declaration = declaration.WithVariables(SyntaxFactory.SingletonSeparatedList(declaration.Variables[0].WithInitializer(SyntaxFactory.EqualsValueClause(startValue))));
id = SyntaxFactory.IdentifierName(declaration.Variables[0].Identifier);
}
else
{
id = (ExpressionSyntax)stmt.ControlVariable.Accept(_nodesVisitor);
var symbol = _semanticModel.GetSymbolInfo(stmt.ControlVariable).Symbol;
if (!_semanticModel.LookupSymbols(node.FullSpan.Start, name: symbol.Name).Any())
{
var variableDeclaratorSyntax = SyntaxFactory.VariableDeclarator(SyntaxFactory.Identifier(symbol.Name), null,
SyntaxFactory.EqualsValueClause(startValue));
declaration = SyntaxFactory.VariableDeclaration(
SyntaxFactory.IdentifierName("var"),
SyntaxFactory.SingletonSeparatedList(variableDeclaratorSyntax));
}
else
{
startValue = SyntaxFactory.AssignmentExpression(SyntaxKind.SimpleAssignmentExpression, id, startValue);
}
}
var step = (ExpressionSyntax)stmt.StepClause?.StepValue.Accept(_nodesVisitor);
PrefixUnaryExpressionSyntax value = step.SkipParens() as PrefixUnaryExpressionSyntax;
ExpressionSyntax condition;
if (value == null)
{
condition = SyntaxFactory.BinaryExpression(SyntaxKind.LessThanOrEqualExpression, id, (ExpressionSyntax)stmt.ToValue.Accept(_nodesVisitor));
}
else
{
condition = SyntaxFactory.BinaryExpression(SyntaxKind.GreaterThanOrEqualExpression, id, (ExpressionSyntax)stmt.ToValue.Accept(_nodesVisitor));
}
if (step == null)
{
step = SyntaxFactory.PostfixUnaryExpression(SyntaxKind.PostIncrementExpression, id);
}
else
{
step = SyntaxFactory.AssignmentExpression(SyntaxKind.AddAssignmentExpression, id, step);
}
var block = SyntaxFactory.Block(node.Statements.SelectMany(s => s.Accept(CommentConvertingVisitor)));
return(SingleStatement(SyntaxFactory.ForStatement(
declaration,
declaration != null ? SyntaxFactory.SeparatedList <ExpressionSyntax>() : SyntaxFactory.SingletonSeparatedList(startValue),
condition,
SyntaxFactory.SingletonSeparatedList(step),
block.UnpackNonNestedBlock())));
}
public override SyntaxList <StatementSyntax> VisitForBlock(VBSyntax.ForBlockSyntax node) => AddLocalVariables(node);
public override Task <SyntaxList <StatementSyntax> > VisitForBlock(VBSyntax.ForBlockSyntax node) => AddLocalVariablesAsync(node, VBasic.SyntaxKind.ForKeyword, true);
public override Task <SyntaxList <StatementSyntax> > VisitForBlock(VBSyntax.ForBlockSyntax node) => AddLocalVariablesAsync(node);